Lasers chelate

From the first synthesis of rare-earth /9-diketonates in 1897 by Urbain until now, hundreds of different complexes formed by reaction between Lnni ions and /3-diketone derivatives have been described in the literature. Interest for this type of complexes comes from then-potential application in numerous and diverse domains. These complexes can be used for example as extractants in solvent-solvent extraction processes or as active compounds for the development of chelate lasers or liquid lasers. But they can also find applications in NMR as shift reagents or as electroluminescent materials in organic light-emitting diodes (OLEDs) (Binnemans, 2005b). 

Having completed our survey of the chemical aspects of the chelate laser, we now proceed to examine the energy transfer and loss mechanisms in these systems. 

Lempicki (14J lists several ligands, cations, and solvents commonly used for rare-earth chelate lasers. As in glasses, the wavelengths of transitions exhibit small shifts with changing ligand or cation (15). 

Neodymium chelate laser action at 300 K was obtained, but to reduce nonradiative decay of 3/2, a ligand containing... 

EuAopium. This is the most extensively studied chelate laser ion. Trivalent Eu has lased in 24 organic chelate solutions at temperatures ranging from -150 to 30°C. Some of the ligands, cations, and solvents used are given in Ref. 

There is one report of optically-pumped Tb + chelate laser action at room temperature the threshold was very high (70). 

Rare earth laser action has been obtained for two groups of liquids metallo-organic and inorganic aprotic liquids. The first group are chelate lasers and are reviewed by Lempicki and Samelson (1966) research on aprotic materials and systems for high-power, pulsed liquid lasers are reviewed by Samelson and Kocher (1974). Stimulated emission in both liquids occurs between 4f states of trivalent rare earths. Optical pumping is via xenon-filled flashlamps in optical cavities and resonators similar to those used in solid-state lasers. Rare earth liquid lasers have only been operated pulsed. 

Rare earth chelate lasers. See Lempicki (1971) for details of ligands and solvents used. 

Potential upper laser levels are limited to those having a large energy gap to the next-lower level because of the large probability for non-radiative quenching in chelate laser solutions. 

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